Foldable chalkboard



May 15, 1962 H. A. WINDRAM 3,034,230

FOLDABLE CHALKBOARD Filed Nov. 20, 1959 2 Sheets-Sheet 1 2 '1 'zi'a Hora/d A. mhdram INVENTOR.

BY m, 5%

May 15, 1962 H. A. WINDRAM 3,034,230

FOLDABLE CHALKBOARD Filed Nov. 20, 1959 2 Sheets-Sheet 2 u I 82 F/g.3 20 80 2 iv QR Harold A. W/hdram 1N VEN TOR.

BY fizmaafh.

3,034,230 FOLDABLE CHALKBOARD Harold A. Windram, 2nd St. SW. Ext, Carrollton, Ohio Filed Nov. 20, 1959, Ser. No. 854,448

' 11 Claims. (CI. 35-64) This invention relates to a foldable chalkboard and more particularly to mechanical and structural improvements in foldable chalkboards.

An object of the invention is to provide structural improvements and refinements in folding or foldable chalkboards.

Although there have been foldable chalkboards proposed in the past, the foldable chalkboard in accordance with the invention provides a substantial improvement over all prior chalkboards.

An important feature of the invention is found in the fact that the chalkboard may be folded and unfolded without the disadvantage of a crack or space between the panels at the juncture thereof to mar an otherwise smooth surface. Obviously, a crack is necessary where rigid panels are used, but the crack is completely concealed in a chalkboard in accordance with the invention and provides no difficulty in writing thereover.

Another important feature of the invention is found in the manner of hinging the panels and the locking device associated therewith.

The invention is embodied in a foldable chalkboard having two or more panels, providing surfaces that are hinged together. Although a chalkboard is mentioned as the preference, it is to be clearly understood that the principles of the invention are equally well applicable wherein any two surfaces are better joined together with the crack therebetween completely concealed. For example, game boards could well use the principles of the invention.

The chalkboard may be mounted on foldable or extensible legs and may accommodate one or more flexible coverings to convert the chalkboard to a photographic projection screen or to serve as a flannelgraph.

Although a two panel construction is sufiicient to exemplify the principles of the invention, it is to be clearly understood that the panels may be made in multiples of two, three or more with very minor modifications and still following the principles of the invention.

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout, and in which:

FIGURE 1 is a perspective view of a folding chalkboard in an open position demonstrating one possible configuration of the invention.

FIGURE 2 is a perspective view of the chalkboard in a folded position.

FIGURE 3 is a sectional view taken on the line 3-3 of FIGURE 1.

FIGURE 4 is a fragmentary elevational view of a hinge constituting an important part of the invention.

FIGURE 5 is a sectional view taken on a line 55 of FIGURE 4.

FIGURE 6 is a sectional view showing the hinge as it would appear in the closed position.

FIGURE 7 is an enlarged fragmentary detail sectional view showing one possible Way of holding a cover panel in an extended position over the front face of the chalkboard.

FIGURE 8 is a schematic view merely indicating the fact that the principles of the invention are not restricted to a folding chalkboard having only two panels.

3,ll34,23i} Patented May 15, 1%62 C ice In the accompanying drawings there is illustrated a foldalble chalkboard 10 in an open position (FIGURE 1) and in a closed position (FIGURE 2). Legs 12 and 14 are optional, and the type of legs is subject to wide variation. Legs 12 and 14 are very simple, being essentially T-shaped and connected by screw threading into openings in frame 16 of the chalkboard.

Structurally, chalkboard It} is quite simple. It includes two panels 18 and 20 of comparatively rigid material, for instance plyboard, composition board or others. Two essentially U-shaped frame sections 22 and 24 are joined to three edges of the respective panels 18 and 20. The panels may be inset (FIGURE 3) in routed or otherwise formed recesses such as grooves in one face of the U-shaped frame sections and held in place by standard fastening means. The confronting edges of the frame sections are open so that when the chalkboard is in the open position (FIGURE 3) the frame 26 constructed of the two frame sections 22 and 24 is rectangular and continuous, providing the appearance of a single rectangular frame.

Panels 18 and 20 are preferably a laminate of panel boards, a thin flexible metal panel 28 (for magnetic at traction and to cover the crack between panels 18 and 26) and a writing surface forming panel 30. The flexible metal panel may be made of very thin steel or other elastic metal capable of being folded and then returned to a flat position, uncreased, by the folding procedure. The writing surface forming panel 30 may be made of linen or cotton which is treated to provide a writing surface. Treated windowshade material which of itself, is conventional, serves the purpose very well. The metal panel 28 and the panel 30 are each unbroken i.e. they are formed in one piece covering both panels 18 and 20 when in the open position (FIGURE 3). Panel 30 is securely glued to panels 18 and 29 except for a short distance to each side of the confronting edges of panels 18 and 20. When panel 28 is used, it is similarly connected to panels 18 and 2t and panel 30 is secured there- 1110.

Identical upper and lower hinges 32 and 33 are used to join frame sections 22 and 24 at the confronting ends thereof. Typical hinge 32 is made of two flexible metal straps 34 and 36 secured by adjustable anchors at the ends thereof to the upper members of frame sections 22 and 24. Typical anchor 35 is made of a screw 88 extending through an opening in the upper member of frame section 22 and terminating in a guide aperture 40 formed in fixed member 42 located in the recess 44 concealed within the upper frame member of section 22. Nut 46 is on the threaded part of screw 38 and is spot welded or otherwise secured to one terminal part of strap 34.

The strap 34 has an angulated end 48 to which nut 46 is secured and which is located in the recess or cavity 44. By adjusting screw 38, the tension of strap 34 may be correspondingly adjusted. The two straps extend over nosings 50 and 52 at the arcuate confronting edges 54 and 56 of the confronting sections 22 and 24.

Control link 60 is set in a slot 62 having parts in both of the confronting ends of sections 22 and 24. Spindles 64 and 66 extending through apertures in guide link 60 form fulcrums' for the guide link and they are in the plane of panel 30.

Looking device 70 is operatively connected with the guide link and it holds the panels in the extended position and also in the folded position as shown in FIG- URES 5 and '6, respectively. Locking device 74) consists of a bar 71having a tongue 72 extending from one surends of the upper members of V 3 surface of bar 71. The bolt is mechanically secured by a clamping member 76 to the link 69. Use of the locking device entails loosening and tightening the wing nut 75 to bring the bar 71 in firm contact with the confront ing edges of the upper members of sections 22 and 24 or the rear faces of the same members. I Optionally, the rear face, of the chalkboard may be used as a bulletinboard. Further, one or more optional rollers 79 and 80 may be attached to the end members of sections 22 and 24-. Housing supports 81 and 82 are secured to the rear-surfaces of these members and shade rollers are mounted therein. The shade rollers may contain various types of coverings for the chalkboard. For example, one of the shade rollers may contain a photographic screen and the other a flannelgraph panel. Numerous ways of holding the auxiliary panels over the front face of the chalkboard may be resorted to, one of which is shown in FlGURE 7 This seems to be a very simple method, consisting of a stop 83 secured to one end of one of the sections and constituting means by which to engage an aperture 84 of the auxiliary panel. Other ways of securing the auxiliary panels in place are obviously possible.

FIGURE 8 shows a multiple panel chalkboard 10a, but this is merelya diagrammatic representation and is not intended to be a full structural presentation. The panels are hingedly connected together very much the same as the panels of chalkboard. 10, and the four illustrated panels (FIGURE 8) may be opened to an extended position or closed as shown.

The foregoing is considered, as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly all suitable modifications and equivalents may be resorted to, falling within the scope of the invention as claimed.

What is claimed as new is as follows:

1. A folding chalkboard comprising .a first frame section, a second frame section, said frame sections having adjacent open ends which confront each other, said frame sections cooperating to form one continuous frame when said sections are arranged in tandem, hinge means connecting adjacent ends of said frame sections, panels carried by said frame sections, and flexible covering means over said panels to conceal the crack between said panels, said flexible covering means including a metallic panel which is flexible and which functions to effectively cover the crack between the first mentioned panels and also to serve as a magnetic base for magnetic attraction thereto.

2. A folding chalkboard comprising a first frame section, a second frame section, said frame sections having adjacent open ends which confront each other, said frame sections cooperating to form one continuous frame when said sections are arranged in tandem, hinge means connecting adjacent ends of said frame sections, panels carried by said frame sections, and flexible covering means over said panels to conceal the crack between said panels, said flexible covering means including a metallic panel whichis flexible and which functions to effectively cover the crack between the first mentioned panels and also to serve asa magnetic base for magnetic attraction thereto, and 'awriting surface flexible panel over said metallic panel.

3. A-folding chalkboard comprising a first panel supporting frame section, a second panel supporting frame section, said frame sections having adjacent open ends which confront each other, said frame sections cooperating to form one continuous frame when said sections are arranged in tandem, hinge means connecting adjacent means connected at said hinge means for selectively holding said panels in an extended and in a folded position, said locking means including a locking bar, adjustable fastening means connected with said locking bar and with a portion of one of said hinges for drawing said locking bar tightly against the adjacent portions of said frame sections, said bar being operatively engageable selectively with one side of the panels or'with said adjacent ends thereof.

4. A foldable chalkboard comprising a pair of panels, means including links hingedly connecting one end of the panels, threaded shanks on said links at right angles thereto, bars adjustably mounted on the shanks and operatively engageable selectively with said one end of the panels or with one side thereof for locking same in folded or unfolded position, and nuts threaded on the shanks for engaging the bars with the panels.

5. A foldable chalkboard comprising a pair of panels, means hingcdly connecting the panels at one end for relative swinging movement to open and closed positions, and means for releasably locking the panels in either position, the first-named means including bolts rotatably mounted on the panels, nuts threadedly mounted for adjustment on said bolts, andcrossed, flexible connecting straps each having one end anchored to one of the panels and its other end affixed to one of said nuts on the other panel for adjustment thereby.

6. A foldable chalkboard comprising a pair of panels,

7 means hingedly connecting the panels at one end for relative swinging movement to open and closed positions,

and means for releasably locking the panels in either p0- s'ition, the first-named means including bolts rotatably mounted on the panels, nuts threadedly mounted for adjustment onsaid bolts, and crossed, flexible connecting straps each having one end anchored to one of the panels and its other end afiixed to one of said nuts on the other panel for adjustment thereby, the second-named means including a link having its end portions pivotally connected to the panels, a threaded shank on said link at an intermediate point, an adjustable bar on said shank operatively engageable selectively with one side of the panels or with said one end thereof for retaining same in said open or Said closed position, and a nut threaded on the shank for engaging the bar with the panels.

7. A foldable chalkboard comprising, in combination,

a pair of panels, means pivotally connecting one end of said panels for swinging movement to open and closed positions, means operatively connecting the panels for swinging movement in unison, and means for releasably locking the'panels in open and closed positions.

8. A foldable chalkboard in accordance with claim 7, wherein said panels have opposed slots in the pivotally connected end portions thereof, the first-named means including a link having its end portions pivotally anchored in said slots.

9. A foldable chalkboard in accordance with claim 8, wherein the third-named means includes a threaded shank fixed on the link. at an intermediate point and at right angles thereto, abar on the shankoperatively engageable selectively with one side of the panels or with said one end thereof, and a nut threaded on the shank for clamping the bar against the panels.

10. A'foldable chalkboard in accordance with claim '7, wherein the second-named means includes a pair of flexible straps each having one end anchored to one of the panels, said straps being crossed and having their other end anchored to the other panel. I

11. A foldable chalkboard in accordance with claim 10, wherein said second-named means further includes screws rotatably mounted on the panels and threadedly connected to the straps for adjusting same.

References Cited in the file of this patent UNITED STATES PATENTS 7 241,367 Hyatt et al. May 10, 1881 7 (Other references on following page) UNITED STATES PATENTS Grubb Nov. 18, 1890 Bullard May 8, 1906 Whalen May 13, 1924 Townsend Feb. 21, 1928 Gandrud Mar. 1, 1938 Young Jan. 15, 1952 Fleming May 22, 1956 Stec Sept. 15, 1959 FOREIGN PATENTS 7 France Ian. 5, 1935 Germany Feb. 11, 1928 Switzerland Aug. 1, 1934 

